Dyed cellulosic textiles are commonly used in making a large variety of products, e.g., denim jeans. One class of denim are garments and articles which are characterized as overdyed denim. These products are produced by subjecting a warp dyed denim with undyed fill yarn to a further dyeing step. The further dyeing step imparts to the denim a particular color tint which is introduced by the dye, which is especially evident from the fill yarn. This further dyeing step acts to primarily dye the fill yarn of the desized denim but also imparts some degree of dyeing to the previously dyed warp yarn. Producing overdyed denim garments and articles requires that the desized denim is contacted in a dye bath with a selected dye under appropriate conditions. For such dyeing operations, direct dyes as defined in the Colour Index are generally used. The denim containing products are contacted with the direct dye in a bath under conditions which are dictated by the direct dye selected. These conditions are generally at a temperature in the range of 85.degree.-95.degree. C., for a period of about 0.5-2.5 hours in an aqueous bath which typically further includes an effective amount of a salt generally to provide a bath concentration of 5-40 g of salt per liter of bath. Typical dye baths have a pH in the range of 7-8.5.
U.S. Pat. No. 5,469,966 discloses a process for the treatment of denim textiles by contacting the denim textile with a cellulase in the presence of a dye to impart a stone-washed and overdyed effect on the denim textile.
It is an object of the present invention to provide an improved enzymatic method for overdyeing fabrics and articles.